Our efforts this year have been devoted primarily to the continuation and expansion of several projects described in detail in our FY 1979 Annual Report. We have applied our recently developed GC-MS assay for pentamethylmelamine to studies of the phase I pharmacology of this drug in cancer patients. Several lines of investigation are ongoing in the area of drug-induced pulmonary injury. Long-term toxicity and/or carcinogenicity studies centered primarily upon the lung-toxic furans are in progress. The roles of glutathione in drug-induced tissue injury continues to be a major interest. The role of the drug-metabolizing enzymes in the pathogenesis of chemical-induced injury to extrahepatic target cells, such as pulmonary Clara cells and renal proximal tubular cells, continues to be a major area of endeavor.